Curwensville Lake is a 790 acre impoundment located on the West Branch Susquehanna River about 8 miles southwest of the town of Clearfield. The dam was completed in 1965 by the U.S. Army Corps of Engineers. The reservoir is one of four impoundments used for flood control in the West Branch Susquehanna River watershed. Aside from the purpose of flood control, the reservoir also provides water supply storage and fishing and boating opportunities. The Curwensville Lake Recreation Area surrounding the reservoir is managed by Clearfield County.

Fisheries Management Area 3 staff conducted trap net and night electrofishing surveys at Curwensville Lake during the week of May 18, 2009. Trap nets were fished at 12 locations for a total of 279.5 hours. A night electrofishing survey was conducted on the night of May 19th and included 4 sites. Prior to 2009, the Curwensville Lake fishery was last surveyed by the PFBC in 1998.

Seventeen fish species were collected during trap netting and Table 1 includes our catches of the most abundant game fish species. In addition to those species listed in Table 1, we also collected walleye, largemouth bass, common carp, rock bass, white suckers, redhorse suckers, golden shiners, green sunfish, and 3 tiger muskellunge ranging from 32 to 37 inches.

The night electrofishing survey conducted on May 19th targeted walleye, largemouth bass, smallmouth bass, and tiger muskellunge (Table 1). Black bass (smallmouth and largemouth) catch rates during the 2009 survey were nearly 7 times greater than the previous survey conducted in 1998 (Figure1). Walleye catches were also good and improved considerably from the previous survey. In 2004, CARP (Curwensville Angler’s Restocking Program) began a walleye stocking program and these plantings likely contributed to our walleye catches.

Table 2. Length-frequency distribution of black bass, walleye, and tiger muskellunge collected during the night electrofishing survey on May 19th.

Size in inches

Largemouth Bass

Smallmouth Bass

Walleye

Tiger Muskellunge

5

1

6

7

8

8

6

1

9

1

3

10

3

7

1

11

4

7

12

6

3

4

13

13

1

15

1

14

15

3

15

9

1

1

16

5

1

1

17

1

18

2

19

1

//

28

1

Totals

60

38

26

2

Figure 1. Mean CPUE (number/electrofishing hr) of black bass collected at Curwensville Lake in 1998 and 2009. Note the significant increase in catches of all sizes of bass from 1998 to 2009.

Curwensville Lake has shown considerable improvement as a fishery over the past decade and the improvements can likely be attributed to two major factors. In 1997 the U.S. Army Corps of Engineers implemented a “no winter draw down” water-level management plan. This allowed for a stable pool elevation during most of the year and consistent year-round shallow water (littoral) habitat. In addition, water quality has likely improved due to acid mine drainage remediation efforts in the West Branch Susquehanna River watershed upstream of the lake. Thus, it is likely a combination of improved habitat and water quality that have resulted in the significant improvements in the reservoir’s sport fish populations.